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Rotel Amplifier Problem

 
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pauly
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PostPosted: Tue Sep 20, 2005 6:19 am    Post subject: Rotel Amplifier Problem Reply with quote

My Rotel RA-940BX amplifier has stopped working and I would like to try and fix it myself. Has anyone got any experience of Rotel amps? When switched on, I used to be able to hear an audible click after a couple of seconds from within the amp . It wasn't until this click was heard that any sound would come out of the speakers. However, when I now switch it on there is no click and nothing seems to be working. I've taken the cover off and had a good look around and there is nothing obviously faulty. The transformer output is correct, 28.3V. The only component I can see which might have been the source of the click is a 24V relay, could this be the problem?

Thanks,
Paul
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[email protected]
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PostPosted: Tue Sep 20, 2005 10:34 am    Post subject: ROTEL AMP REPAIR Reply with quote

Hi Paul,
saw yr msg on esi.com. Check 12 V / 24 V DC which power up the relay ckt thru a time delay C-R ckt.disconnect the load(speaker wires) before you do this.It could be a fusible resistor blown or some problem in
the DC power supply.pl reply ASAP for further help.what about.rotel.com
e service? Best regards, Raj
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PostPosted: Wed Sep 21, 2005 7:23 am    Post subject: Reply with quote

Hi Raj,

Thanks for your reply. I powered up the amp and checked the voltage across the relay and it is 0V. It looks like you could be right and it is the power supply to the relay where the problem is. Without a cct diagram I am not sure where on the board the CR delay cct is likely to be. I checked the output from the DC bridge after the transformer output and this seems to working ok. I did send an email to Rotel asking for help but they didn't reply. Any more ideas?
Thanks,
Paul
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AUDIODON
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PostPosted: Wed Oct 05, 2005 5:01 pm    Post subject: Re: Rotel Amplifier Problem Reply with quote

pauly wrote:
My Rotel RA-940BX amplifier has stopped working and I would like to try and fix it myself. Has anyone got any experience of Rotel amps? When switched on, I used to be able to hear an audible click after a couple of seconds from within the amp . It wasn't until this click was heard that any sound would come out of the speakers. However, when I now switch it on there is no click and nothing seems to be working. I've taken the cover off and had a good look around and there is nothing obviously faulty. The transformer output is correct, 28.3V. The only component I can see which might have been the source of the click is a 24V relay, could this be the problem?

Thanks,
Paul


Hi Paul

The reason the relay won't work is because the protection circuit is on !!
This is because there is DC at the output which will burn out your speakers or the rest of the amplifier if you force it to work.

AUDIODON
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Jubei
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PostPosted: Tue Mar 13, 2007 1:12 pm    Post subject: Rotel RA-940BX Reply with quote

Guys I'm desperately trying to find this amplifier's operating manual. Any ideas where I can find it?

I'm trying to find what kind of speakers I can connect to it (how many Ohms).

Nick
Greece
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polaret



Joined: 23 Oct 2004
Posts: 90
Location: greece

PostPosted: Tue Mar 13, 2007 5:28 pm    Post subject: Reply with quote

Hi this seems to be short cirquit in the output stage
and the relay doesnt work because is in protect
disconect the output stage TR or mosfet or IC and try to power on if the relay works it is sure short cirquit
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